Balun design to connect two differential ports into one single ended 50ohm

[dz99]

Hi Guys,

Any of you have an idea how to solve this problem without the use of RF switcher?
The classical way would be to use two separate baluns + RF swticher, but here that doesn'T works, need a simpler solution.

Any article, book, advise are welcome!

Thanks

 

[BigBoss]

Two Baluns and a power combiner/duplexer will solve your problem.
If the frequencies are different, a Diplexer can also be used.

 

[dz99]

Two Baluns and a power combiner/duplexer will solve your problem.
If the frequencies are different, a Diplexer can also be used.

2.4GHz
2x2cm PCB with on board IC (diff. tx and rx ports)
possible lowest BOM required
low insertion loss required, but RF switcher too expensive,Wilkinson divider too big(possibly), resistive divider too lossy

so this is why I'm scared )

Am I right that the smallest Wilkinson divider (pcb) is in this freq is in the scale of 1.5...2cm (lambda/4 size with FR4 shortening factor)?

 

[BigBoss]

2.4GHz
2x2cm PCB with on board IC (diff. tx and rx ports)
possible lowest BOM required
low insertion loss required, but RF switcher too expensive,Wilkinson divider too big(possibly), resistive divider too lossy

so this is why I'm scared )

Am I right that the smallest Wilkinson divider (pcb) is in this freq is in the scale of 1.5...2cm (lambda/4 size with FR4 shortening factor)?

If the PCB dimensions are 2x2cm, you will have to use miniaturized commercial components.It can be more expensive or less..
Otherwise, you can not realize this circuit on that surface with FR4.

For Baluns, look at Murata
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But if TX and RX frequencies are same, the only way is to use either switch or PIN diodes or small GaAs switches.
Peregrine Semiconductors produce very small profile and high isolation/isolation switches.You'd better look at ..
**broken link removed**